Unzip all bz2 files

The backup program storeBackup saves some files in the bz2 format. The following command makes such folders usable.

Piwik Upgrade

It is not possible to upgrade an old instance of piwik to the latest version in one step.

I took the following steps:
– 0.9 -> 1.0
– 1.0 -> 2.0
– 2.0 -> 2.14
– 2.14 -> 2.17
– 2.17 -> 3.0

Everytime all files except for config/config.ini need to be deleted.